Line the base and sides of a 24cm round or square cake pan with parchment paper.
Gently heat butter, sugar and all the fruits in a non-stick pan until the sugar dissolves. Add the lemon and orange rind and stir in the fruit juices. Bring to a gentle simmer for 810 minutes. Remove the pan from the heat. Dish out mixture into a bowl and leave aside to cool completely. Add in the almonds.
Sift the flours into the cooled fruit mixture to mix. Stir in the beaten eggs to combine. Add the brandy or rum and mix well.
Turn out mixture into the prepared pan. Use a spatula to level the batter.
Bake in a pre-heated oven at 150°C for 1¼1½ hours or until the cake is cooked through when tested with a wooden skewer.